Abstract
Purpose: :
To analyze the incidence and management of bacterial keratitis in Rhode Island in the past seven years in the context of emerging bacterial resistance.
Methods: :
Bacterial keratitis records at Rhode Island Hospital (RIH) were reviewed for patient demographics, etiology, initial/modified therapy, and outcomes. Corneal ulcer specimen reports were reviewed for causative organisms, susceptibility testing results, and prevalence of resistance.
Results: :
Bacterial keratitis was diagnosed in 46 patients. Of all initial treatments, 84% involved fluoroquinolones and 31% were modified due to resistance. Patients had previously used general ocular antibiotics in 37% of cases. There were 60 total identified organisms, most commonly coagulase negative Staphylococcus species (45.0%). There was a 4:1 ratio of gram-positive to gram-negative organisms. Coagulase negative Staphylococcus increased in cefazolin resistance, and Pseudomonas aeruginosa was consistently sensitive to ciprofloxacin except in 2003. Two cases of fourth generation fluoroquinolone resistance and postoperative MRSA keratitis were identified.
Conclusions: :
Coagulase negative Staphylococcus species and Pseudomonas aeruginosa are the most common causative organisms of bacterial keratitis in Rhode Island. This study shows prior corticosteroid use/immunosuppression to be a significant risk factor, possibly due to its tertiary hospital setting. Third-generation fluoroquinolone resistance is a significant concern in determining treatment especially with patients who receive fluoroquinolones as monotherapy, and newer, more effective fourth-generation fluoroquinolones should be considered in treating bacterial keratitis.
Keywords: keratitis • bacterial disease • antibiotics/antifungals/antiparasitics